Muni bonds represent a compelling source of yield for insurers

Muni bonds represent a compelling source of yield for insurers

The municipal bond market is a $3.7 trillion source of funding for states and cities throughout the US. Historically, this market has drawn little attention from foreign investors, but this is now changing due to the appealing properties of revenue bonds. This subset of the wider municipal bond market is backed by revenue streams from infrastructure providers, such as electricity utilities and toll roads, and may therefore qualify as infrastructure assets under Solvency II. This would enable insurers to pick up competitive spreads for securities with a low historical default experience whilst benefiting from favourable capital charges.

In this article, we set out what attracts insurers to the revenue bond market, and in particular, how this sector offers an accessible alternative to traditional infrastructure investment, whilst outlining some of the key considerations around implementing an allocation within a fixed income portfolio.

Market overview

The municipal bond market has long been attractive for many US investors on account of the tax-free benefits of most securities, meaning that the income earned by bondholders is not subject to federal or state income taxes. As a result of this favourable tax treatment, market yields on tax-exempt municipal bonds are typically lower than similar-quality taxable bonds (e.g., corporate bonds). Tax-exempt municipal bonds are generally inefficient investments for an investor who is not subject to US income taxes and who therefore cannot benefit from the tax advantages of these instruments. However, not all municipal bonds have tax-exempt status. The issuance of taxable municipal bonds boomed following the enactment of the Build America Bonds programme in 2009, which was designed to stimulate the US economy in the wake of the financial crisis. Issuers were able to tap a much broader investor base, including investors not subject to US income taxes, who were attracted to these bonds paying a higher interest rate, for which the US Treasury compensated the issuer.

At the end of July 2016, the Bloomberg Barclays Taxable Municipal Bond Index comprised 373 issuers with a market value of $323 billion, which can be broadly split into two types of credit: 

  • General obligation bonds, backed by the taxing powers and credit of the issuing state and local governments
  • Revenue bonds, backed by revenues from infrastructure-type assets, such as toll roads, airports, health care providers and utilities.

Infrastructure characteristics

It is the second of these two categories, revenue bonds, that is attracting interest from insurers looking to benefit from favourable yields and capital charges. Revenue bonds make up 67% of the index with tax & lease, utilities and transportation representing the largest sectors (see Figure 1). The potential for revenue bonds to qualify as infrastructure investments under EIOPA’s criteria stems from their predictability of cash flows, the ability to meet financial obligations under a variety of scenarios and stress tests, as well as the protection afforded by the contractual frameworks in place. Revenue bond offering documents often include rate covenants that dictate the circumstances under which rates must be adjusted to meet payments; for example, if a toll road financed by a revenue bond failed to cover debt service by a required margin, the bond trustee could force the toll authority to raise usage fees. Overall, revenue bonds are a high quality asset class with a readily accessible market. This is an attractive quality at a time when the supply to market of traditional infrastructure is not keeping up with demand.

Frustration with traditional infrastructure

It has long been argued that insurers are a natural fit to finance long-dated infrastructure loans. However, the pipeline of private infrastructure projects has remained limited with anemic economic conditions resulting in many governments reducing their infrastructure spending. In addition to limited supply, insurers are also faced with extensive due diligence requirements to understand the key risks underpinning the cash flows for each project as well as evidencing a deep understanding of the different types of projects spanning the infrastructure universe. Also, the liquidity profile of private infrastructure entails committing capital longer than other alternatives to traditional corporate bond allocations. By comparison, revenue bonds offer many of the same infrastructure characteristics while also benefiting from a relatively more liquid market and less intensive due diligence requirements.

ALM and Solvency II considerations

In addition to these benefits, revenue bonds offer a stable cash-flow profile and duration of around 9-10 years, which can be useful for ALM purposes. At the end of July 2016, AA rated revenue bonds provided a yield of 2.8%, which compares favourably to 1.5% yield from US Treasuries, 0.7% from UK gilts and -0.1% from German bunds. The recent potential decrease in capital charges by around 30% for infrastructure debt also makes this an attractive and capital-efficient option when compared to corporates with similar ratings and maturities, as shown in Figure 2 and Figure 3.

Overall, we believe that revenue bonds serve as an excellent diversifier to a traditional corporate credit allocation. Municipal credits typically perform well later in the broader credit cycle because changes in municipal issuer revenues tend to trail overall economic activity. Revenue bonds also offer attractive value versus corporates of a comparable quality, particularly in light of the significantly lower historical default rates experienced by municipal bonds (see Figure 4).

Implementing an allocation to revenue bonds

The revenue bond market is relatively small with less frequent issuance, which lends itself to a relatively concentrated allocation that should complement existing corporate credit holdings. With this role in mind, designing an allocation should allow for opportunistic buying with a focus on the sectors that offer a superior risk/reward profile relative to corporate bonds. The market also has relatively low liquidity and is fairly shallow, so careful selection is important and a long investment time horizon is necessary.

In addition, as the large issuance of Build America Bonds from 2009 – 2010 ages, we expect market activity to gradually decline, and sourcing and selling bonds could become more difficult. This argues for a buy-and-hold mentality, and for accumulating bonds whenever attractive offerings become available.

In conclusion, we believe revenue bonds are a compelling option for insurers seeking infrastructure-type investments. The high quality, long duration cash flows, with attractive capital charges and accessible implementation, means we have seen interest growing among European insurers. Wellington Management is one of the largest investors in the revenue bond market and has the skills, depth of resources and extensive broker networks required to effectively manage allocations for our insurance clients.

For additional information, please contact:

Bob Sharma, Insurance Relationship Manager, London (44-20-7126-6068;

Susanne Ballauff, Business Development Manager, Frankfurt (49-69-677761-502; 

Ray Helfer, Director Global Relationship Group, APAC, Hong Kong (852-2846-6006;

Eric Tanaka, Director Financial Reserves Management, Boston (01-617-263-4040;


Bob Sharma, Insurance Relationship Manager, Wellington Management

James Bradbury, Insurance Relationship Manager, Wellington Management

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